SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '499727f4a2c356e03a9775775c57711a1f0a99feb100091accdc2db098428bb2' 
  AND token = 'T7HFExU8DL+VuNsGeNDDSKUOGK3jLNoJ53ntKGHE2Dg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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