SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '7ab679d2ab5c247a985fa4bd9e6cb2759adad824f39399ed3fb13260d1b7e0bb' 
  AND token = 'tGgVYWDqHH0PjHin5C06prlilKdg+UBT7ZU2mrE8iTg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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