SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd3ca80dd72393332cff4de34fefb3a0cd6dccc7d349a7e620506ac5415cda8c2' 
  AND token = 'ANoc2UBbqUv7qAFpQwQ5WusVX1222kgQA8UZf24e9bM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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