SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0f315fb12fcbabd740a15f261c4607e01dcb2b0db0aac664eef74c92a78bdfd9' 
  AND token = 'xP+N9+imSY42ZqG9CMhSAtthzTeWIlalMj+io2p2kz0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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