SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3d7308f288d1fd4a82f65511331f1c22f9305dcc56baf776ab90112a318dcff0' 
  AND token = 'e8yKW9iJw/O88V0QPY/d7gs17A+3a6CYNlgtRgFATyA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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