SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ec9cd94b99e9e0a3bd9053b72e1bdd36b17a704d0d4d2e31a1f1cffd33ec211b' 
  AND token = 'uCG6cRsViTtR0biRKoTyzndcPPWGzHkKFwVUYkewONQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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