SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '16e61496b801d070f407b3ea2b3e132ba73defd49ee144e491b3bd5472638897' 
  AND token = 'G4rE5Pf8xDCSnSN4xU4JCmXvD2gHCCXjyRtxbGP9MKc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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