SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bc803219e96f2ce434b0ceb9809a0f46cbfc079dae6fcdbc9114b47f8120640e' 
  AND token = 'eZyxJVMUsvHi8IzKw31UHDq/g20O1GX05JhTp1fSZ3g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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