SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05e9320fd40c1af4440c4271e1d2c005dc33a203bfeb427ed4b2a912f247253b' 
  AND token = 'kBe2KDyTYdhnwYV/fsUO/5ltacOqDkNt4XhVSPbKOQQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}