SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac80e8dd6f2d1482fd959577e6eeadc20ae032a4a0cc2de9e0f01c437b3dee63' 
  AND token = 'Kr7FzLUEKGEcW4jL2jIIog6oQVwoXOix7Uzlg23icko=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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