SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f1800fbe6b04c6828308da251378e9194331884882dfd715618e33c1c3dfd0f0' 
  AND token = 'Re7U+uDPXVugPz+3grYapYCX03+o8dbaDu0kOa9bi5Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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