SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6187def46fa61741209693ec550c23cb015e18ca4fbf7f0f2a9e23967bd602b7' 
  AND token = 'KEhpYBz0g2XHBUK4vVnmoIhYPx/5InMU+knZU/WV/sE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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