SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1558747ade3262e91023e6b6cd11286f5486c080b657cc5c3150ae903f3cf88a' 
  AND token = 'rwO/cdPbclZlma2+ExBy0gfFAcatnYMM2LoUgk/IXcA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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