SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b60f79e29b48a4be474586d515f49a1a5229b1be3b0adc9f5169a1a7b420106a' 
  AND token = 'Dc6WBzgYxJp9dZ1WQwbtnHpC3nbqracsvsWZqRpSVGk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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