SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0b00bd08216c80a10ee46bca7e9a5fae6da7da371d945267b781867646b07386' 
  AND token = 'DCLjtODVkXYy27vUAaRqPkjkbN5XJjX5FlZ1im3Wtj4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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