SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '49e3a1a99ae20091fa228d3a2457557aecd24dacdd6019d96c21b70edaabd997' 
  AND token = 'k3LOYeW5R6eXCeC5GeAc1/jDU/bpzERfDDSVl25kbE8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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