SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bb2a9127eff17dc85fbe413443a45b0f2c7f61c5f9647454b4d476750c8931ba' 
  AND token = 'v9GlSj1XFbJfBO4Kz1yxZ7pnXlTFjU4cjFzvo5bFOtI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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