SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa3a6269d1df048a9b26755a1570e885da442a5024eabacb237dfbc531d6892e' 
  AND token = 'nf8PJ6MLwP5mluZVRMKtm0npxkwW7Uhsr7uUEk91v1o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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