SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4f3a5064384ab45f3020ba83639f836629b206171ec7112fbef3ed9f6910d287' 
  AND token = 'ktYZ07g75wLRX3QKZwGWaYWIMvV13mqQxjCbvj6OlyI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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