SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3c1d5d0a794cecb6479f3a1580a0985a037ee840e528541d68e3846f18cd12cd' 
  AND token = 'eEXY1n+wSV4f2gJS0ikdSKrq+uBmXQWJ21wgkISiuqY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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