SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '73aebcca66a9f4ded3a45cb952a247a6daeae4eaac0fd8230207efb35257d2ce' 
  AND token = '3EOqMjnezF+gv2ebAXkpbTh8Zrc/IahiJiN/JvVBs3s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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