SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd9b0049dc4e8ab58ba0133dd12835e9a68a8190d9ca01413764aaffcf2f390f1' 
  AND token = 'PTcH1rZymruRQUcTEWlPTh+zZzI+ZNQYhftNParMUTA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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