SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58ddbf007e47609514fcbf45142dd19314f6d93fac7993ba8d923f1719c1e23e' 
  AND token = 'NfXF0CnXK7Bk6hkHmfhStbvkdH2kDF3iy2NOmH3rLFM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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