SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '042110ea07f39822a352142814f2c851cf9905d3c052ee15ffedd63d363656d7' 
  AND token = 'jt7NZKNM62wqTwuinPjCZVJp6L9Go5ea3OlNMHYK+FM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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