SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fd44da237a6b55a66cf51d054fae49eba5f3238e883dac9bc28def674029c67a' 
  AND token = 'nXKjPKSBxQCfRpodn25G7HKzE0j2gv9A9fB8GFYn+Zk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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