SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed4d72ccc8b2e9574102b3f108dba5f09989a39a32f5db89652cbe4b8476db02' 
  AND token = 'AvFkmSymMX8a7JCzAmp+BNSHUv51hBjjg3yFR1PK+vE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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