SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6a907b2abc6657f7850678283beef027787bcb1c040ce218fe9872df7cd6a3ed' 
  AND token = 'XPwvWbvYW3s7jSdaU8Hc8YRun1un91jDyL9EQPtssds=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}