SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '31698e589bf500928b4f9921eb26c1ba0b3e19927922f2c359abc58a4479e410' 
  AND token = '+WbBHV1xFEcFFY2M+BBQVEaS/v9KIMyQ9//8Ob8s1Ek=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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