SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7185424bba5022b3437c0c7f71b6cbf31a4ddfaa4463da95709d23d06b2371b5' 
  AND token = 'knr5+OcxrDgKgXPZ/M+rz52sXPYNuAaiii5KE/OYrqA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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