SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '90e27b22067e57019c5216fbc3637e45536c2dee756f337d59dd6308fd634870' 
  AND token = 'FILL8Cxu152kvIx1+QmpKxA/33VGY9KuMaOWe9ah/Ns=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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