SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c4ede786fe040df7a64bbb7725cdb01a7f141938a5b1295cf2b894d2877c4d6d' 
  AND token = '4WOZrR5k1hUPqed8+tYQNw5n/boBL7K5AwB+UuuML+0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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