SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e74584cc9e95ebb4d62ff86178517caeaf0340d7bc37483f0e916fea349b8c1c' 
  AND token = 'jgesAsJdSnyo818YBisFa5pGd83iIxORPs4J6gnodSc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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