SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7e8d4db9c7da0d526620327a1ae60fc74d5c9675cf635a004f9a15d471febfc1' 
  AND token = 'eO0xugOUA/iV3C00Q5dcpHP4ONrWYjfQwDj7bVIbgLQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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