SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '97b58f91bcf2d92ca307c816b8dd181ec2b2cb6edc0077885a37e4cd43f3a59c' 
  AND token = '6CsK7bpohQKP4vw+/ivzaM9Zsbj6ZoSeevtJGKlkOb4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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