SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '42b4ecd68bd6ed67bb6dc2887e23d1cd165d457fff24ec5054074e2ce76d34e8' 
  AND token = 'q9O2VCTtzCYPgJfwVmlXusdzZfZtIKOZjCoRlHN8SFE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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