SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9695170b728f654aef936d28dac820b92df510d6ed7a45e84de010603b3e3175' 
  AND token = 'vNZNpfzYVbJvCTpBly0hp9vvGovjD0KYkc2hiWJJlBw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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