SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ea260abdbca20c0e7490ffad7ff3f920551949a9703eb98791f87f8cc80c8983' 
  AND token = '+RDRq1ldRq3rL32rCrjr88Q2PrEXh5KLnbJU2gHWoE8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00060

JSON explain

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