SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '66d954ad0f7dc56a12d37cb6e30e32a87992400f5fd513f05d09351461b45945' 
  AND token = 'AlknR4p3MoD30vXwe9U4z3tlgcwStHTHirdFFXIbzBg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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