SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8d9bf960ff73494e925db444e6e1cceb64b57f5cb1630d78314e9db190fc7de0' 
  AND token = 'ZK6x5IY2A2AolBQdL5effD2ChxtoAD+A/3Bfa15J3zA=' 
  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"
    }
  }
}