SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bbbbc96b8f0f9b457f00acaab9b4329fe28cc0aece631282223b1af5a9da81f5' 
  AND token = 'JYevs+O/DuAzFSqGxWWJwxyQOHIQ2xmeZdnE2AwgQ+E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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