SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a2f8255dd80d47d57d4370fe73ac1942d7e2a6be326853869677d5971ad271b' 
  AND token = 'J30/a67Tr0BTGCuRsBTUSyfO/jvzqnOLdqH4pj8IjVw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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