SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9c92c8845484a14044828cc68c55c5090ecb64729848e7ccb6f2d26d4c8d00b1' 
  AND token = 'YZH0v2KRqy6kWw5dWlZ9w+/xjc41IvbHCbpghqol4Ss=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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